He did say it was a car striped of it's parts. No telling what was left to start with.
Maybe it was just a chassis to start, no body?
I have to admit I am no expert on the GT40 history.
There wasn't many Mark 4's made, I thought maybe 5. Number 1 is in the Ford Museum in Detriot.
I think that's an ERA license plate mount in the rear. We have a guy in St. Louis with a brown ERA GT40 (nice car BTW) that has that same mount as I remember.